The adjustable bimodal random exchange interaction effects on the mixed spin-(12,1) Blume-Capel Quantum model with biaxial crystal field: A mean-field approximation calculations

The magnetic and thermodynamic properties of the Blume-Capel model are investigated within an approach combined with quantum mechanics and mean-field approximation for the spin-1/2 and spin-1 with coordination number z = 3. The spin-1 sites are subjected to transverse crystal fields D-x and D-y. In addition, the bilinear interaction parameter J is randomly distributed with an adjustable parameter alpha>0 such that certain sites are under the influence of alpha J with probability p while the rest are subject to J with probability 1-p. The thermal behaviors of the order parameters have been studied to determine the nature of phase transitions and to calculate phase diagrams in the (D-x,kT), (D-y,kT),(alpha,kT),(|J|,kT), and (p,kT) planes. The obtained results revealed a rich variety of critical phenomena including first- and second-order phase transitions, tricritical points, and compensation temperatures. Under an external magnetic field, the system exhibits both simple and multi-hysteresis behaviors. Furthermore, the coercive field and remanent magnetization decrease with increasing temperature.